Resuscitator



H. SEELER RESUSCITATOR Filed April 1, 1952 INVENTOR. A/t-MPVJEfZA-Z? laxM 4 1 Feb. 28, 1956 United States Patent RESUSCITATOR Henry Seeler,Dayton, Ohio, assignor to the United States of America as represented bythe Secretary of the Air Force Application April 1, 1952, Serial No.279,906

7 Claims. (Cl. 137-63) (Granted under Title 35, U. S. Code (1952), sec.266) The invention described herein may be manufactured and used by orfor the United States Government for governmental purposes withoutpayment to me of any royalty thereon.

The present invention relates to a resuscitator having novel means foradjusting the inhalation and exhalation pressures.

The principal object of the invention is to provide a resuscitatorincluding an aspirator into which flows a gas under pressure suitablefor use in resuscitating human patients and wherein a butterfly valvewithin the aspirator is actuated to open and closed positions by anovercenter spring means and by a pressure actuated means associated witha slidable rod and wherein a separate yieldable force producing means atopposite endS of the slidable rod includes a permanent magnet andarmature capable of relative rotation to vary the attractive forcebetween the magnet and armature.

A further object of the invention is to provide a resuscitator of thekind which includes an aspirator or Venturi tube in which flows a gasunder pressure suitable for use in resuscitating human patients, whereina butterfly valve in the aspirator downstream from a lateral openingtherein is rigidly connected to a simple crank operating means, whereina coil spring connected to the crank operating means is actuated by aslidably mounted rod fixed to a diaphragm, wherein adjustable magneticforce producing means are provided at opposite'ends of the slidablymounted diaphragm-actuated rod and wherein a gas flow channel in theresuscitator is in communication with the lateral opening in theaspirator, with a tube leading to a face mask and with one side of therodactuating diaphragm, whereby the butterfly valve when brought to openposition by the diaphragm and slidably mounted rod, acting through thecoil spring and crank operating means, functions to produce theexhalation phase of the resuscitation cycle and when brought to closedposition functions to produce the inhalation phase of the resuscitationcycle.

The above and other objects of the invention will become apparent uponreading the following detailed description in conjunction with theaccompanying drawing, in which:

Fig. l is a side elevation view partly in cross section of the presentresuscitator.

Fig. 2 is a front elevation view partly in cross section of the presentresuscitator.

Fig. 3 is a rear elevation view partly in cross section of the presentresuscitator.

Fig. 4 is a longitudinal cross section taken through the aspirator andassociated control valve.

Referring to the drawing the resuscitator will be described in detail.The main body 1 is of generally cylindrical shape and is closed at oneend by a screw threaded cap or cover plate 2 having small openings 3therein. An annular shoulder within the body provides a seat for acircular wall member 4, a circular diaphragm 5 and a circular gasket 6in series and these elements are scribed in detail.

retained by the screw cap 2. The wall member 4 includes a cylindricalextension 7 having its rim edge seated against a flat end wall of thebody 1, as at 8. Outwardly of the extension 7 the wall member 4 ispierced by a series of openings 9. An actuating rod 10 centrally of thehousing 1 is slidably guided by means of openings in the housing walland in the end cap or cover 2. The rod 10 is rigidly fixed to a pair ofdiaphragm supporting plates or disks 11. At opposite ends of the rod 10are similar bar-like armatures 12 and 13 of soft iron in threadedengagement with the rod. These armatures are free to turn on the ends ofrod 10 so that their relative positions with respect to a pair ofcircular permanent magnets 14 and 15 may be varied to provide a biasingmeans. The magnets, which each have a central passage therethrough, arepress fitted into acircular recess in the housing 1 and in the threadedcap 2. Each magnet is of Alnico and is magnetized in a bi-polar patternas indicated by the letters N and S in Fig. 2. Thus the armature 12 inFig. 2 is in a position for maximum attraction toward the magnet andtherefore a maximum force would be required to move the armature awayfrom the magnet when it is contacted therewith. However any rotation ofthe armature 12 away from the position shown in Fig. 2 will diminish theattractive force between the armature and magnet and if there is arelation between the armature and the opposite magnetic poles the forcewill be very little if any at all. The magnetic effect in the magnetfans out slightly from the exact bi-polar pattern, so that the magneticforce between the armature and magnet merely diminishes as the armatureis rotated from the maximum force position illustrated. Exactcalibration of the force producing arrangement is accomplishedexperimentally, since there are many variables in any design. Forinstance the relative width of the armature is critical because thearmature is influenced very markedly as long as any of the metal thereofis close to the bi-polar axis extending from the letter N to the letterS.

The construction at opposite sides of the housing is similar and onlythat at the right of Fig. 1 will be de- The magnet 14 and armature 12are housed in a flanged cylinder 16 rotatably mounted on the housing 1by means of a ring bearing 17 rigidly connected to the housing 1.Mounted in the cylinder 16 is a small U-shaped bracket 18 which fitsover one end of the armature 12, so that rotation of the cylinder 16causes rotation of the armature 12. An aperture in the outer end of theflanged cylinder 16 is closed by a thin rubber disk 19 held in place byan apertured cap 20 which is knurled on the outer cylindrical surface.Rotation of the cylinder 16 and armature 12 is accomplished by graspingthe knurled cap 20 and turning in one direction or the other. Thepurpose of the rubber disk 19 is to permit finger operation of the pushrod 10 in case of failure of the rod actuating means or in case ofsticking of the parts. With one hand an operator may span theresuscitator and exert alternate force on the opposite ends of the pushrod to cycle the rod back and forth at a prescribed breathing rate. Inorder to indicate the exact relative position of the armature 12, apointer 21 is fixedon the cylinder 16 and extends out through a thinrecess in the bearing ring 17 to indicate on a quadrant 22 the angularposition of the armature 12 with reference to the bi-polar axis N-S.

A supply of oxygen or compressed air at about +10 inches of water (gagepressure) enters the resuscitator at the tubular fitting 23, having arotatable sleeve 24 mounted thereon. An inner sleeve 25 which rotateswith the sleeve 24 includes opposite cam slots into which the oppositeends of the crosspin 26 extend (see Fig. 3,). A

tapered valve element 27 fixed on pin 26 has a T-shaped passage thereinto permit a minimum flow of gas even when the valve element 27 is fullyseated on the beveled valve seat 28' of the nozzle 28. The latter isflanged outwardly for retention in the housing 1 by means of anaspirator tube 29. The tube is in turn held in place by a threaded tubemember 30. The aspirator includes the usual Venturi formation 29'therein and also a plurality of spill ports 31 upstream from the Venturiformation. Downstream from the Venturi formation 29 is a butterfly valveor cycling valve 32 mounted for rotation on one end of a crank 33. Theother or ofiset end of the crank has a tension spring 34 hookedthereover and the spring extends through a suitable opening in aflattened portion 10 on the push rod 10. An outlet connection 35 on thehousing 1 is used to connect the resuscitator to a suitable face mask(not shown). It is further noted that the outer end of tube 31) is opento the atmosphere but may be covered by a small circular screen 36retained in place by a snap ring 37.

The operation of the resuscitator will be explained by reference toFigs. 1 to 4. Noting Fig. l first it will be seen that the valveactuating diaphragm is shown in the extreme right-hand position ofdisplacement with the left-hand armature 13 contacting the permanentmagnet 15. The butterfly valve 32 is now open and the aspirator isacting to produce suction Within the resuscitator and in the fitting 35.This suction eflect continues until the patients lungs are substantiallyempty of air and gaseous products of respiration. The pressure on theleft-hand side of the diaphragm now goes below atmosphere andatmospheric pressure acting on the right-hand side of the diaphragmfinally pushes the diaphragm to the left as the armature 13 is pushedfree of the magnet 15. The force that will be required to free thearmature from the magnet Will depend on the relative rotative positionof the armature with respect to the N-S polar axis of the magnet.Therefore the degree of negative pressure which will develop during theexhalation phase of the resuscitation cycle will depend on the rotativesetting of the armature 13. Also it should be noted that once thearmature is pushed free of the magnet the attractive force declinesrapidly. Thus the rod moves suddenly and causes a decisive action of thecrank 33 and overcenter spring 34, so that the butterfly valve 32rapidly rotates to a new position.

Assuming now that the valve 32 has snapped to the closed position (Fig.4), with the crank 33 and spring 34 in the dotted line position of Fig.1, oxygen flow is now possible only through the spill ports 31 and intothe resuscitator housing. This oxygen flow now reaches the patientslungs by way of the fitting 35 and a suitable conduit. The armature 12will now be in contact with the magnet 14 and will be retained thereonby a force dependent on the position of the armature with respect to theN-S polar axis of the magnet. As the oxygen fills up the patients lungs,the pressure in the resuscitator increases rapidly to thus increase thepressure on the lefthand side of diaphragm 5 above atmosphere. When thedifferential force thereon exceeds the holding force of the magnet 14 onthe armature 12, the armature is suddenly pushed tree of the magnet. Thedegree of positive pressure which develops during the inhalation phasewill depend on the rotative adjustment of the armature 12 with respectto the magnet 14. The armature 12 being pushed free of the magnet 14,the rod 11) moves to the right causing spring 34 to move to the rightpast the axis of rotation of the crank 33 and valve '32. The spring nowcauses the valve 32 to snap to open position again to start anotherexhalation phase of the resuscitation cycle.

The cycling rate of the resuscitator will depend on the rate of oxygenflow into the aspirator by way of the fitting 23, since filling of thelungs will depend on the flow of oxygen out through the spill ports 31into the resuscitator housing 1. Emptying of the lungs beingaccomplished by suction developed by the aspirator, the rate of emptyingwill depend on the rate of flow of oxygen through the aspirator. Thus itwill be seen that the cycling rate of the resuscitator will be dependenton the setting of the flow control valve 27 reciproeably mounted in thefitting 23. Even with the valve element 27 fully seated on the valveseat 28', a bare minimum flow can take place through the T-shapedpassage in element 27.

The present application embodies improvements over the resuscitatordisclosed in my U. S. Patent No. 2,581,450 of January 8, 1952.

The embodiment of the invention herein shown and described is to beregarded as illustrative only and it is to be understood that theinvention is susceptible of variations, modifications and changes withinthe scope of the appended claims.

I claim:

1. A resuscitator comprising, a housing defining a gas receivingchamber, means providing a gas inlet into said housing, means providinga gas outlet from said housing into the ambient atmosphere, meansproviding a fitting on a wall of said housing connecting with saidchamber and adapted for connection with a face mask, an aspiratorextending across said housing from said gas inlet to said gas outlet andincluding spill ports opening laterally from the aspirator into said gasreceiving chamber, a movably mounted valve in said aspirator downstreamfrom said ports, valve operating means connected to said valve andextending outside of said aspirator, a reciprocably mounted means insaid housing, means responsive to changes in pressure in said chamberfor moving said reciprocably mounted means in opposite directions as thepressure in said chamber rises and falls, means connected between saidvalve operating means and said reciprocably mounted means to actuatesaid valve from closed to open position and vice versa as saidreciprocably mounted means is moved in opposite directions by the actionof rising and falling pressure in said chamber, separate adjustablebiasing means acting in opposition on said reciprocably mounted meansfor biasing the latter means in opposite directions, and each of saidbiasing means including a magnet and an armature adjacent thereto, eachof said magnets having opposed magnetic poles on opposite sides of thereciprocably mounted means providing a polar axis transverse to thereciprocably mounted means, said magnet and said armature beingrotatably adjustable with respect to each other between a positionwherein the armature lies in a plane parallel to the plane of the polaraxis to produce a maximum holding force of the magnet on the armature toa position wherein the armature lies in a plane perpendicular to theplane of the polar axis to produce a minimum holding force of the magneton the armature.

2. A resuscitator comprising, a housing defining a gas receivingchamber, means providing a gas inlet into said housing, means providinga gas outlet from said housing into the ambient atmosphere, meansproviding a fitting on a wall of said housing connecting with saidchamber and adapted for connection with a face mask, an aspiratorextending across said housing from said gas inlet to said gas outlet andincluding spill ports opening laterally from the aspirator into said gasreceiving chamber, a movably mounted valve in said aspirator downstreamfrom said ports, valve operating means connected to said valve andextending outside of said aspirator, a slidably mounted rod in saidhousing, means responsive to changes in pressure in said chamber formoving said rod in opposite directions as the pressure in said chamberrises and falls, spring means connected between said valve operatingmeans and said rod to actuate said valve from closed to open positionand vice versa as said rod is moved in opposite directions by the actionof rising and falling pressure in said chamber, separate adjustablebiasing means at opposite ends of said rod for biasing said rod inopposite directions, and each of said biasing means including a magnetand an armature adjacent thereto, each of said magnets having opposedmagnetic poles on opposite sides of the rod providing a polar axistransverse to the rod, said magnet and said armature being rotatablyadjustable with respect to each other between a position wherein thearmature lies in a plane parallel to the plane of the polar axis toproduce a maximum holding force of the magnet on the armature to aposition wherein the armature lies in a plane perpendicular to the planeof the polar axis to produce a minimum holding force of the magnet onthe armature.

3. In a resuscitator, a cycling valve, means to actuate said valve fromopen to closed position and vice versa including a slidably mountedelement, separate adjustable biasing means acting in opposition on saidslidably mounted element and associated therewith for biasing saidelement in opposite directions, and each of said biasing means includinga magnet and an armature adjacent thereto, each of said magnets havingopposed magnetic poles on opposite sides of the element providing apolar axis transverse to the element, said magnet and said armaturebeing rotatably adjustable with respect to each other between a positionwherein the armature lies in a plane parallel to the plane of the polaraxis to produce a maximum holding force of the magnet on the armature toa position wherein the armature lies in a plane perpendicular to theplane of the polar axis to produce a minimum holding force of the magneton the armature.

4. In a resuscitator, a cycling valve, means to actuate said valve fromopen to closed position and vice versa including a slidably mounted rod,an armature rotatably mounted on each end of said rod, a magnet adjacentto each of said armatures and alternately contacted by the respectivearmatures as said rod is moved back and forth to accomplish the movementof said cycling valve each of said magnets having opposed magnetic poleson opposite sides of the rod providing a polar axis transverse to therod, each of said armatures being rotatable with respect to itsrespective magnet between a position wherein the armature lies in aplane parallel to the plane of the polar axis to produce a maximumholding force of the magnet on the armature to a position wherein thearmature lies in a plane perpendicular to the plane of the polar axis toproduce a minimum holding force of the magnet on the armature.

5. In a resuscitator, a housing having a pair of opposite parallelwalls, a slidably mounted rod extending through said pair of walls,actuating means inside said housing and connected to said rod foractuation of a resuscitation cycling valve, an armature on each end ofsaid rod outside of said pair of walls, a magnet adjacent to each ofsaid armatures and alternately contacted by the respective armature assaid rod is moved back and forth to accomplish movement of said cyclingvalve, each of said magnets having opposed magnetic poles on oppositesides of the rod providing a polar axis transverse to the rod, and eachof said armatures being relatively rotatable with respect to itsrespective magnet be tween a position wherein the armature lies in aplane parallel to the plane of the polar axis to produce a maximumholding force of the magnet on the armature to a position wherein thearmature lies in a plane perpendicular to the plane of the polar axis toproduce a minimum holding force of the magnet on the armature.

6. In a resuscitator, a slidable valve actuating rod, actuating meansfor said rod, an iron armature rotatably mounted on said rod, apermanent magnet adjacent to said armature and surrounding said rod,said magnet having opposed magnetic poles on opposite sides of the rodproviding a polar axis transverse to the rod, and said armature beingrelatively rotatable between a position wherein the armature lies in aplane parallel to the plane of the polar axis to produce a maximumholding force of the magnet on the armature to a position wherein thearmature lies in a plane perpendicular to the plane of the polar axis toproduce a minimum holding force of the magnet on the armature.

7. In a device of the class described, a slidably mounted rod, controlmeans operable to move said rod, an armature rotatably mounted on eachend of said rod, a pair of ring shaped magnets encircling said rod andlocated closer to each other than said armatures so as to be alternatelycontacted by the respective armatures as said rod is moved back andforth, each of said magnets having opposed magnetic poles on oppositesides of the rod providing a polar axis transverse to the rod, each ofsaid armatures being rotatable with respect to its respective magnetbetween a position wherein the armature lies in a plane parallel to theplane of the polar axis to produce a maximum holding force to a positionwherein the armature lies in a plane perpendicular to the plane of thepolar axis to produce a minimum holding force of the magnet on thearmature.

References Cited in the file of this patent UNITED STATES PATENTS152,444 Westland June 23, 1874 2,547,171 Prouty Apr. 3, 1951 2,575,906Bullard Nov. 20, 1951 2,581,450 Seeler Ian. 8, 1952 2,609,835 HorvaySept. 9; 1952

